Chronic myocardial infarction: Assessment of morphology, function, and perfusion by gradient echo magnetic resonance imaging and 99mTc-methoxyisobutyl-isonitrile SPECT

Assessment of Myocardial Viability With Contrast-Enhanced Magnetic Resonance Imaging

“…However, these wall-thickness parameters had only limited diagnostic value for differentiation between viable and scar tissue (Figure 4). In contrast to previous investigations, 17,18 remodeling processes may have altered LV geometry in our patient population with severely dilated ventricles, so that these parameters did not allow the detection of viable myocardium.…”

“…Prognosis may be altered without changing LV function by improving LV remodeling processes, thus preventing additional LV dilatation, promoting electrical stability, and reducing risk of subsequent fatal ischemic events. 7,16 Besides scintigraphic and echocardiographic methods, MRI offers various parameters of tissue viability, such as wall thickness and wall thickening, 17,18 contractile reserve, 19 and hyperenhancement. 8,9,20 This study is, to our knowledge, the first direct comparison of MRI hyperenhancement with PET in patients with ischemic heart failure.…”

“…10 After initial transmission scanning for attenuation correction, rest myocardial perfusion imaging with 13 N-ammonia (NH3) (740 MBq) was performed. After allowing for NH3 decay, 18 Ffluorodeoxyglucose (FDG) (370 MBq) was injected, and data acquisition was initiated 40 minutes after tracer injection. Transaxial planes were obtained using a whole-body PET (ECAT EXACT or HRϩ, Siemens/CTI).…”

ECG-gated multi-detector row spiral CT in the assessment of myocardial infarction: correlation with non-invasive angiographic findings

“…The apparently normal wall thickness of the infarcted segments found in all patients (n=9) with a recent event can be interpreted as another indirect CT sign of myocardial edema and might be a useful criterion to differentiate recent (<1 month) from non-recent (>1 month ) MI, since myocardial wall thickness constantly decreases over time in patients with MI [25,26]. Myocardial edema gradually resolves, being constantly replaced by progressive wall thinning of the LV due to healing of the infarcted region and to left ventricular remodeling [24,27].…”

“…Myocardial edema gradually resolves, being constantly replaced by progressive wall thinning of the LV due to healing of the infarcted region and to left ventricular remodeling [24,27]. However, although wall thinning is a typical feature of chronic infarctions, this finding is not observed in non-transmural infarctions [25].…”